Active antenna

A local EAS detection device comprising:

• at least one local transmitting antenna for receiving sequentially generated signal bursts from a central remote circuit and transmitting the signal bursts into an interrogation zone;
• a receiver associated with said at least one local transmitting antenna for detecting the presence of an electronic tag in the interrogation zone by means of a return tag signal from the electronic tag and transmitting the return tag signal to the central circuit;
• a synchronization device for detecting the signal burst transmitted from said at least one local transmitting antenna, the synchronization device controlling the activation of the receiver for the purpose of receiving the return tag signal based on the timing of the signal burst;
• a differential amplifier, a band pass filter amplifier, and a Tx burst sensor;
• switches for controlling the differential amplifier, band pass filter amplifier, and Tx burst sensor;
• and
• a microprocessor (MCU) to provide timing control of the switches.